text: /*
   * Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the OpenSSL license (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include "internal/cryptlib.h"
  #include <openssl/engine.h>
  #include <openssl/evp.h>
  #include <openssl/x509v3.h>
  #include "internal/asn1_int.h"
  #include "internal/evp_int.h"
  #include "internal/numbers.h"
  
  typedef int sk_cmp_fn_type(const char *const *a, const char *const *b);
  
  static STACK_OF(EVP_PKEY_METHOD) *app_pkey_methods = NULL;
  
  static const EVP_PKEY_METHOD *standard_methods[] = {
  #ifndef OPENSSL_NO_RSA
      &rsa_pkey_meth,
  #endif
  #ifndef OPENSSL_NO_DH
      &dh_pkey_meth,
  #endif
  #ifndef OPENSSL_NO_DSA
      &dsa_pkey_meth,
  #endif
  #ifndef OPENSSL_NO_EC
      &ec_pkey_meth,
  #endif
      &hmac_pkey_meth,
  #ifndef OPENSSL_NO_CMAC
      &cmac_pkey_meth,
  #endif
  #ifndef OPENSSL_NO_DH
      &dhx_pkey_meth,
  #endif
      &tls1_prf_pkey_meth,
  #ifndef OPENSSL_NO_EC
      &ecx25519_pkey_meth,
  #endif
      &hkdf_pkey_meth
  };
  
  DECLARE_OBJ_BSEARCH_CMP_FN(const EVP_PKEY_METHOD *, const EVP_PKEY_METHOD *,
                             pmeth);
  
  static int pmeth_cmp(const EVP_PKEY_METHOD *const *a,
                       const EVP_PKEY_METHOD *const *b)
  {
      return ((*a)->pkey_id - (*b)->pkey_id);
  }
  
  IMPLEMENT_OBJ_BSEARCH_CMP_FN(const EVP_PKEY_METHOD *, const EVP_PKEY_METHOD *,
                               pmeth);
  
  const EVP_PKEY_METHOD *EVP_PKEY_meth_find(int type)
  {
      EVP_PKEY_METHOD tmp;
      const EVP_PKEY_METHOD *t = &tmp, **ret;
      tmp.pkey_id = type;
      if (app_pkey_methods) {
          int idx;
          idx = sk_EVP_PKEY_METHOD_find(app_pkey_methods, &tmp);
          if (idx >= 0)
              return sk_EVP_PKEY_METHOD_value(app_pkey_methods, idx);
      }
      ret = OBJ_bsearch_pmeth(&t, standard_methods,
                              sizeof(standard_methods) /
                              sizeof(EVP_PKEY_METHOD *));
      if (!ret || !*ret)
          return NULL;
      return *ret;
  }
  
  static EVP_PKEY_CTX *int_ctx_new(EVP_PKEY *pkey, ENGINE *e, int id)
  {
      EVP_PKEY_CTX *ret;
      const EVP_PKEY_METHOD *pmeth;
      if (id == -1) {
          if (!pkey || !pkey->ameth)
              return NULL;
          id = pkey->ameth->pkey_id;
      }
  #ifndef OPENSSL_NO_ENGINE
      if (pkey && pkey->engine)
          e = pkey->engine;
      /* Try to find an ENGINE which implements this method */
      if (e) {
          if (!ENGINE_init(e)) {
              EVPerr(EVP_F_INT_CTX_NEW, ERR_R_ENGINE_LIB);
              return NULL;
          }
      } else
          e = ENGINE_get_pkey_meth_engine(id);
  
      /*
       * If an ENGINE handled this method look it up. Otherwise use internal
       * tables.
       */
  
      if (e)
          pmeth = ENGINE_get_pkey_meth(e, id);
      else
  #endif
          pmeth = EVP_PKEY_meth_find(id);
  
      if (pmeth == NULL) {
          EVPerr(EVP_F_INT_CTX_NEW, EVP_R_UNSUPPORTED_ALGORITHM);
          return NULL;
      }
  
      ret = OPENSSL_zalloc(sizeof(*ret));
      if (ret == NULL) {
  #ifndef OPENSSL_NO_ENGINE
          ENGINE_finish(e);
  #endif
          EVPerr(EVP_F_INT_CTX_NEW, ERR_R_MALLOC_FAILURE);
          return NULL;
      }
      ret->engine = e;
      ret->pmeth = pmeth;
      ret->operation = EVP_PKEY_OP_UNDEFINED;
      ret->pkey = pkey;
      if (pkey)
          EVP_PKEY_up_ref(pkey);
  
      if (pmeth->init) {
          if (pmeth->init(ret) <= 0) {
              ret->pmeth = NULL;
              EVP_PKEY_CTX_free(ret);
              return NULL;
          }
      }
  
      return ret;
  }
  
  EVP_PKEY_METHOD *EVP_PKEY_meth_new(int id, int flags)
  {
      EVP_PKEY_METHOD *pmeth;
  
      pmeth = OPENSSL_zalloc(sizeof(*pmeth));
      if (pmeth == NULL)
          return NULL;
  
      pmeth->pkey_id = id;
      pmeth->flags = flags | EVP_PKEY_FLAG_DYNAMIC;
      return pmeth;
  }
  
  void EVP_PKEY_meth_get0_info(int *ppkey_id, int *pflags,
                               const EVP_PKEY_METHOD *meth)
  {
      if (ppkey_id)
          *ppkey_id = meth->pkey_id;
      if (pflags)
          *pflags = meth->flags;
  }
  
  void EVP_PKEY_meth_copy(EVP_PKEY_METHOD *dst, const EVP_PKEY_METHOD *src)
  {
  
      dst->init = src->init;
      dst->copy = src->copy;
      dst->cleanup = src->cleanup;
  
      dst->paramgen_init = src->paramgen_init;
      dst->paramgen = src->paramgen;
  
      dst->keygen_init = src->keygen_init;
      dst->keygen = src->keygen;
  
      dst->sign_init = src->sign_init;
      dst->sign = src->sign;
  
      dst->verify_init = src->verify_init;
      dst->verify = src->verify;
  
      dst->verify_recover_init = src->verify_recover_init;
      dst->verify_recover = src->verify_recover;
  
      dst->signctx_init = src->signctx_init;
      dst->signctx = src->signctx;
  
      dst->verifyctx_init = src->verifyctx_init;
      dst->verifyctx = src->verifyctx;
  
      dst->encrypt_init = src->encrypt_init;
      dst->encrypt = src->encrypt;
  
      dst->decrypt_init = src->decrypt_init;
      dst->decrypt = src->decrypt;
  
      dst->derive_init = src->derive_init;
      dst->derive = src->derive;
  
      dst->ctrl = src->ctrl;
      dst->ctrl_str = src->ctrl_str;
  }
  
  void EVP_PKEY_meth_free(EVP_PKEY_METHOD *pmeth)
  {
      if (pmeth && (pmeth->flags & EVP_PKEY_FLAG_DYNAMIC))
          OPENSSL_free(pmeth);
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e)
  {
      return int_ctx_new(pkey, e, -1);
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_new_id(int id, ENGINE *e)
  {
      return int_ctx_new(NULL, e, id);
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_dup(EVP_PKEY_CTX *pctx)
  {
      EVP_PKEY_CTX *rctx;
      if (!pctx->pmeth || !pctx->pmeth->copy)
          return NULL;
  #ifndef OPENSSL_NO_ENGINE
      /* Make sure it's safe to copy a pkey context using an ENGINE */
      if (pctx->engine && !ENGINE_init(pctx->engine)) {
          EVPerr(EVP_F_EVP_PKEY_CTX_DUP, ERR_R_ENGINE_LIB);
          return 0;
      }
  #endif
      rctx = OPENSSL_malloc(sizeof(*rctx));
      if (rctx == NULL)
          return NULL;
  
      rctx->pmeth = pctx->pmeth;
  #ifndef OPENSSL_NO_ENGINE
      rctx->engine = pctx->engine;
  #endif
  
      if (pctx->pkey)
          EVP_PKEY_up_ref(pctx->pkey);
  
      rctx->pkey = pctx->pkey;
  
      if (pctx->peerkey)
          EVP_PKEY_up_ref(pctx->peerkey);
  
      rctx->peerkey = pctx->peerkey;
  
      rctx->data = NULL;
      rctx->app_data = NULL;
      rctx->operation = pctx->operation;
  
      if (pctx->pmeth->copy(rctx, pctx) > 0)
          return rctx;
  
      rctx->pmeth = NULL;
      EVP_PKEY_CTX_free(rctx);
      return NULL;
  
  }
  
  int EVP_PKEY_meth_add0(const EVP_PKEY_METHOD *pmeth)
  {
      if (app_pkey_methods == NULL) {
          app_pkey_methods = sk_EVP_PKEY_METHOD_new(pmeth_cmp);
          if (app_pkey_methods == NULL)
              return 0;
      }
      if (!sk_EVP_PKEY_METHOD_push(app_pkey_methods, pmeth))
          return 0;
      sk_EVP_PKEY_METHOD_sort(app_pkey_methods);
      return 1;
  }
  
  void EVP_PKEY_CTX_free(EVP_PKEY_CTX *ctx)
  {
      if (ctx == NULL)
          return;
      if (ctx->pmeth && ctx->pmeth->cleanup)
          ctx->pmeth->cleanup(ctx);
      EVP_PKEY_free(ctx->pkey);
      EVP_PKEY_free(ctx->peerkey);
  #ifndef OPENSSL_NO_ENGINE
      ENGINE_finish(ctx->engine);
  #endif
      OPENSSL_free(ctx);
  }
  
  int EVP_PKEY_CTX_ctrl(EVP_PKEY_CTX *ctx, int keytype, int optype,
                        int cmd, int p1, void *p2)
  {
      int ret;
      if (!ctx || !ctx->pmeth || !ctx->pmeth->ctrl) {
          EVPerr(EVP_F_EVP_PKEY_CTX_CTRL, EVP_R_COMMAND_NOT_SUPPORTED);
          return -2;
      }
      if ((keytype != -1) && (ctx->pmeth->pkey_id != keytype))
          return -1;
  
      if (ctx->operation == EVP_PKEY_OP_UNDEFINED) {
          EVPerr(EVP_F_EVP_PKEY_CTX_CTRL, EVP_R_NO_OPERATION_SET);
          return -1;
      }
  
      if ((optype != -1) && !(ctx->operation & optype)) {
          EVPerr(EVP_F_EVP_PKEY_CTX_CTRL, EVP_R_INVALID_OPERATION);
          return -1;
      }
  
      ret = ctx->pmeth->ctrl(ctx, cmd, p1, p2);
  
      if (ret == -2)
          EVPerr(EVP_F_EVP_PKEY_CTX_CTRL, EVP_R_COMMAND_NOT_SUPPORTED);
  
      return ret;
  
  }
  
  int EVP_PKEY_CTX_ctrl_str(EVP_PKEY_CTX *ctx,
                            const char *name, const char *value)
  {
      if (!ctx || !ctx->pmeth || !ctx->pmeth->ctrl_str) {
          EVPerr(EVP_F_EVP_PKEY_CTX_CTRL_STR, EVP_R_COMMAND_NOT_SUPPORTED);
          return -2;
      }
      if (strcmp(name, "digest") == 0) {
          const EVP_MD *md;
          if (value == NULL || (md = EVP_get_digestbyname(value)) == NULL) {
              EVPerr(EVP_F_EVP_PKEY_CTX_CTRL_STR, EVP_R_INVALID_DIGEST);
              return 0;
          }
          return EVP_PKEY_CTX_set_signature_md(ctx, md);
      }
      return ctx->pmeth->ctrl_str(ctx, name, value);
  }
  
  /* Utility functions to send a string of hex string to a ctrl */
  
  int EVP_PKEY_CTX_str2ctrl(EVP_PKEY_CTX *ctx, int cmd, const char *str)
  {
      size_t len;
  
      len = strlen(str);
      if (len > INT_MAX)
          return -1;
      return ctx->pmeth->ctrl(ctx, cmd, len, (void *)str);
  }
  
  int EVP_PKEY_CTX_hex2ctrl(EVP_PKEY_CTX *ctx, int cmd, const char *hex)
  {
      unsigned char *bin;
      long binlen;
      int rv = -1;
  
      bin = OPENSSL_hexstr2buf(hex, &binlen);
      if (bin == NULL)
          return 0;
      if (binlen <= INT_MAX)
          rv = ctx->pmeth->ctrl(ctx, cmd, binlen, bin);
      OPENSSL_free(bin);
      return rv;
  }
  
  int EVP_PKEY_CTX_get_operation(EVP_PKEY_CTX *ctx)
  {
      return ctx->operation;
  }
  
  void EVP_PKEY_CTX_set0_keygen_info(EVP_PKEY_CTX *ctx, int *dat, int datlen)
  {
      ctx->keygen_info = dat;
      ctx->keygen_info_count = datlen;
  }
  
  void EVP_PKEY_CTX_set_data(EVP_PKEY_CTX *ctx, void *data)
  {
      ctx->data = data;
  }
  
  void *EVP_PKEY_CTX_get_data(EVP_PKEY_CTX *ctx)
  {
      return ctx->data;
  }
  
  EVP_PKEY *EVP_PKEY_CTX_get0_pkey(EVP_PKEY_CTX *ctx)
  {
      return ctx->pkey;
  }
  
  EVP_PKEY *EVP_PKEY_CTX_get0_peerkey(EVP_PKEY_CTX *ctx)
  {
      return ctx->peerkey;
  }
  
  void EVP_PKEY_CTX_set_app_data(EVP_PKEY_CTX *ctx, void *data)
  {
      ctx->app_data = data;
  }
  
  void *EVP_PKEY_CTX_get_app_data(EVP_PKEY_CTX *ctx)
  {
      return ctx->app_data;
  }
  
  void EVP_PKEY_meth_set_init(EVP_PKEY_METHOD *pmeth,
                              int (*init) (EVP_PKEY_CTX *ctx))
  {
      pmeth->init = init;
  }
  
  void EVP_PKEY_meth_set_copy(EVP_PKEY_METHOD *pmeth,
                              int (*copy) (EVP_PKEY_CTX *dst,
                                           EVP_PKEY_CTX *src))
  {
      pmeth->copy = copy;
  }
  
  void EVP_PKEY_meth_set_cleanup(EVP_PKEY_METHOD *pmeth,
                                 void (*cleanup) (EVP_PKEY_CTX *ctx))
  {
      pmeth->cleanup = cleanup;
  }
  
  void EVP_PKEY_meth_set_paramgen(EVP_PKEY_METHOD *pmeth,
                                  int (*paramgen_init) (EVP_PKEY_CTX *ctx),
                                  int (*paramgen) (EVP_PKEY_CTX *ctx,
                                                   EVP_PKEY *pkey))
  {
      pmeth->paramgen_init = paramgen_init;
      pmeth->paramgen = paramgen;
  }
  
  void EVP_PKEY_meth_set_keygen(EVP_PKEY_METHOD *pmeth,
                                int (*keygen_init) (EVP_PKEY_CTX *ctx),
                                int (*keygen) (EVP_PKEY_CTX *ctx,
                                               EVP_PKEY *pkey))
  {
      pmeth->keygen_init = keygen_init;
      pmeth->keygen = keygen;
  }
  
  void EVP_PKEY_meth_set_sign(EVP_PKEY_METHOD *pmeth,
                              int (*sign_init) (EVP_PKEY_CTX *ctx),
                              int (*sign) (EVP_PKEY_CTX *ctx,
                                           unsigned char *sig, size_t *siglen,
                                           const unsigned char *tbs,
                                           size_t tbslen))
  {
      pmeth->sign_init = sign_init;
      pmeth->sign = sign;
  }
  
  void EVP_PKEY_meth_set_verify(EVP_PKEY_METHOD *pmeth,
                                int (*verify_init) (EVP_PKEY_CTX *ctx),
                                int (*verify) (EVP_PKEY_CTX *ctx,
                                               const unsigned char *sig,
                                               size_t siglen,
                                               const unsigned char *tbs,
                                               size_t tbslen))
  {
      pmeth->verify_init = verify_init;
      pmeth->verify = verify;
  }
  
  void EVP_PKEY_meth_set_verify_recover(EVP_PKEY_METHOD *pmeth,
                                        int (*verify_recover_init) (EVP_PKEY_CTX
                                                                    *ctx),
                                        int (*verify_recover) (EVP_PKEY_CTX
                                                               *ctx,
                                                               unsigned char
                                                               *sig,
                                                               size_t *siglen,
                                                               const unsigned
                                                               char *tbs,
                                                               size_t tbslen))
  {
      pmeth->verify_recover_init = verify_recover_init;
      pmeth->verify_recover = verify_recover;
  }
  
  void EVP_PKEY_meth_set_signctx(EVP_PKEY_METHOD *pmeth,
                                 int (*signctx_init) (EVP_PKEY_CTX *ctx,
                                                      EVP_MD_CTX *mctx),
                                 int (*signctx) (EVP_PKEY_CTX *ctx,
                                                 unsigned char *sig,
                                                 size_t *siglen,
                                                 EVP_MD_CTX *mctx))
  {
      pmeth->signctx_init = signctx_init;
      pmeth->signctx = signctx;
  }
  
  void EVP_PKEY_meth_set_verifyctx(EVP_PKEY_METHOD *pmeth,
                                   int (*verifyctx_init) (EVP_PKEY_CTX *ctx,
                                                          EVP_MD_CTX *mctx),
                                   int (*verifyctx) (EVP_PKEY_CTX *ctx,
                                                     const unsigned char *sig,
                                                     int siglen,
                                                     EVP_MD_CTX *mctx))
  {
      pmeth->verifyctx_init = verifyctx_init;
      pmeth->verifyctx = verifyctx;
  }
  
  void EVP_PKEY_meth_set_encrypt(EVP_PKEY_METHOD *pmeth,
                                 int (*encrypt_init) (EVP_PKEY_CTX *ctx),
                                 int (*encryptfn) (EVP_PKEY_CTX *ctx,
                                                   unsigned char *out,
                                                   size_t *outlen,
                                                   const unsigned char *in,
                                                   size_t inlen))
  {
      pmeth->encrypt_init = encrypt_init;
      pmeth->encrypt = encryptfn;
  }
  
  void EVP_PKEY_meth_set_decrypt(EVP_PKEY_METHOD *pmeth,
                                 int (*decrypt_init) (EVP_PKEY_CTX *ctx),
                                 int (*decrypt) (EVP_PKEY_CTX *ctx,
                                                 unsigned char *out,
                                                 size_t *outlen,
                                                 const unsigned char *in,
                                                 size_t inlen))
  {
      pmeth->decrypt_init = decrypt_init;
      pmeth->decrypt = decrypt;
  }
  
  void EVP_PKEY_meth_set_derive(EVP_PKEY_METHOD *pmeth,
                                int (*derive_init) (EVP_PKEY_CTX *ctx),
                                int (*derive) (EVP_PKEY_CTX *ctx,
                                               unsigned char *key,
                                               size_t *keylen))
  {
      pmeth->derive_init = derive_init;
      pmeth->derive = derive;
  }
  
  void EVP_PKEY_meth_set_ctrl(EVP_PKEY_METHOD *pmeth,
                              int (*ctrl) (EVP_PKEY_CTX *ctx, int type, int p1,
                                           void *p2),
                              int (*ctrl_str) (EVP_PKEY_CTX *ctx,
                                               const char *type,
                                               const char *value))
  {
      pmeth->ctrl = ctrl;
      pmeth->ctrl_str = ctrl_str;
  }
  
  void EVP_PKEY_meth_get_init(EVP_PKEY_METHOD *pmeth,
                              int (**pinit) (EVP_PKEY_CTX *ctx))
  {
      *pinit = pmeth->init;
  }
  
  void EVP_PKEY_meth_get_copy(EVP_PKEY_METHOD *pmeth,
                              int (**pcopy) (EVP_PKEY_CTX *dst,
                                             EVP_PKEY_CTX *src))
  {
      *pcopy = pmeth->copy;
  }
  
  void EVP_PKEY_meth_get_cleanup(EVP_PKEY_METHOD *pmeth,
                                 void (**pcleanup) (EVP_PKEY_CTX *ctx))
  {
      *pcleanup = pmeth->cleanup;
  }
  
  void EVP_PKEY_meth_get_paramgen(EVP_PKEY_METHOD *pmeth,
                                  int (**pparamgen_init) (EVP_PKEY_CTX *ctx),
                                  int (**pparamgen) (EVP_PKEY_CTX *ctx,
                                                     EVP_PKEY *pkey))
  {
      if (pparamgen_init)
          *pparamgen_init = pmeth->paramgen_init;
      if (pparamgen)
          *pparamgen = pmeth->paramgen;
  }
  
  void EVP_PKEY_meth_get_keygen(EVP_PKEY_METHOD *pmeth,
                                int (**pkeygen_init) (EVP_PKEY_CTX *ctx),
                                int (**pkeygen) (EVP_PKEY_CTX *ctx,
                                                 EVP_PKEY *pkey))
  {
      if (pkeygen_init)
          *pkeygen_init = pmeth->keygen_init;
      if (pkeygen)
          *pkeygen = pmeth->keygen;
  }
  
  void EVP_PKEY_meth_get_sign(EVP_PKEY_METHOD *pmeth,
                              int (**psign_init) (EVP_PKEY_CTX *ctx),
                              int (**psign) (EVP_PKEY_CTX *ctx,
                                             unsigned char *sig, size_t *siglen,
                                             const unsigned char *tbs,
                                             size_t tbslen))
  {
      if (psign_init)
          *psign_init = pmeth->sign_init;
      if (psign)
          *psign = pmeth->sign;
  }
  
  void EVP_PKEY_meth_get_verify(EVP_PKEY_METHOD *pmeth,
                                int (**pverify_init) (EVP_PKEY_CTX *ctx),
                                int (**pverify) (EVP_PKEY_CTX *ctx,
                                                 const unsigned char *sig,
                                                 size_t siglen,
                                                 const unsigned char *tbs,
                                                 size_t tbslen))
  {
      if (pverify_init)
          *pverify_init = pmeth->verify_init;
      if (pverify)
          *pverify = pmeth->verify;
  }
  
  void EVP_PKEY_meth_get_verify_recover(EVP_PKEY_METHOD *pmeth,
                                        int (**pverify_recover_init) (EVP_PKEY_CTX
                                                                      *ctx),
                                        int (**pverify_recover) (EVP_PKEY_CTX
                                                                 *ctx,
                                                                 unsigned char
                                                                 *sig,
                                                                 size_t *siglen,
                                                                 const unsigned
                                                                 char *tbs,
                                                                 size_t tbslen))
  {
      if (pverify_recover_init)
          *pverify_recover_init = pmeth->verify_recover_init;
      if (pverify_recover)
          *pverify_recover = pmeth->verify_recover;
  }
  
  void EVP_PKEY_meth_get_signctx(EVP_PKEY_METHOD *pmeth,
                                 int (**psignctx_init) (EVP_PKEY_CTX *ctx,
                                                        EVP_MD_CTX *mctx),
                                 int (**psignctx) (EVP_PKEY_CTX *ctx,
                                                   unsigned char *sig,
                                                   size_t *siglen,
                                                   EVP_MD_CTX *mctx))
  {
      if (psignctx_init)
          *psignctx_init = pmeth->signctx_init;
      if (psignctx)
          *psignctx = pmeth->signctx;
  }
  
  void EVP_PKEY_meth_get_verifyctx(EVP_PKEY_METHOD *pmeth,
                                   int (**pverifyctx_init) (EVP_PKEY_CTX *ctx,
                                                            EVP_MD_CTX *mctx),
                                   int (**pverifyctx) (EVP_PKEY_CTX *ctx,
                                                       const unsigned char *sig,
                                                       int siglen,
                                                       EVP_MD_CTX *mctx))
  {
      if (pverifyctx_init)
          *pverifyctx_init = pmeth->verifyctx_init;
      if (pverifyctx)
          *pverifyctx = pmeth->verifyctx;
  }
  
  void EVP_PKEY_meth_get_encrypt(EVP_PKEY_METHOD *pmeth,
                                 int (**pencrypt_init) (EVP_PKEY_CTX *ctx),
                                 int (**pencryptfn) (EVP_PKEY_CTX *ctx,
                                                     unsigned char *out,
                                                     size_t *outlen,
                                                     const unsigned char *in,
                                                     size_t inlen))
  {
      if (pencrypt_init)
          *pencrypt_init = pmeth->encrypt_init;
      if (pencryptfn)
          *pencryptfn = pmeth->encrypt;
  }
  
  void EVP_PKEY_meth_get_decrypt(EVP_PKEY_METHOD *pmeth,
                                 int (**pdecrypt_init) (EVP_PKEY_CTX *ctx),
                                 int (**pdecrypt) (EVP_PKEY_CTX *ctx,
                                                   unsigned char *out,
                                                   size_t *outlen,
                                                   const unsigned char *in,
                                                   size_t inlen))
  {
      if (pdecrypt_init)
          *pdecrypt_init = pmeth->decrypt_init;
      if (pdecrypt)
          *pdecrypt = pmeth->decrypt;
  }
  
  void EVP_PKEY_meth_get_derive(EVP_PKEY_METHOD *pmeth,
                                int (**pderive_init) (EVP_PKEY_CTX *ctx),
                                int (**pderive) (EVP_PKEY_CTX *ctx,
                                                 unsigned char *key,
                                                 size_t *keylen))
  {
      if (pderive_init)
          *pderive_init = pmeth->derive_init;
      if (pderive)
          *pderive = pmeth->derive;
  }
  
  void EVP_PKEY_meth_get_ctrl(EVP_PKEY_METHOD *pmeth,
                              int (**pctrl) (EVP_PKEY_CTX *ctx, int type, int p1,
                                             void *p2),
                              int (**pctrl_str) (EVP_PKEY_CTX *ctx,
                                                 const char *type,
                                                 const char *value))
  {
      if (pctrl)
          *pctrl = pmeth->ctrl;
      if (pctrl_str)
          *pctrl_str = pmeth->ctrl_str;
  }
  